The present invention relates to a winding apparatus for winding a multiply connected air core coil, such as a tracking coil used in an optical pickup for reading signals from an optical information storage disk. The multiply connected air core coil includes two or more air coils of a predetermined length of winding material.
Thus far, air core coils where two or more air coils are connected together and used as a set, such as tracking coils, have been made by cutting a winding material whenever one air coil has been wound.
In the conventional winding apparatus, the winding material is cut whenever the winding operation for one coil is completed. This is done for the following reasons. When the air core coil is produced, the projection portion of the winding core rotates so as to wind the winding material around the projection portion of the winding core. Therefore, if the winding material is not cut before the next winding step, the winding core rotates with the first air core coil completely wound. Thus, the air core coil which has been made is rotated and the next air core coil cannot be made. Therefore, the winding material should be cut to a predetermined length in the conventional winding apparatus. On the other hand, if a member supplying the winding material to the winding core rotates around the winding core, the winding core itself need not rotate. However, if this structure is included in the air coil core winding apparatus, the mechanism becomes extremely complicated.
Further in the conventional winding apparatus, when two or more air coils are connected and used as a set, the winding materials which have been cut must be electrically connected to terminals. Thus, it is necessary to prepare a board for soldering the terminals. Consequently, a solder process is required in addition to the board.